Fellow Amateur --

LET'S LOOK AT ANTENNA TECHNOLOGY REALISTICALLY

For the last 50 years there have been no advances in vertical
"technology" -- a technology consisting of vertical wire, fed at the base,
surrounded by any number of radial wires. To operate multiband, traps had to
be placed at appropriate points to shorten the antenna to a 1/4 wave on
various. Manufacturers extolled their antennas based on "low loss" trap
design, implying their antenna would outperform the others. Yet big signals
on the band did not come from these verticals. DX contacts, with the
vertical's well known low angle radiation, did not happen consistently. The
vertical became a 2nd class citizen used by those with little space, minimal
finances or a need to comply with local restrictions.

If a new amateur asked what antenna to put up, the common response from
another ham was, "put up a dipole". Why? Because a conventional vertical is
the most inefficient, noisy antenna available for amateur use and the trap
version is even worse.

WHERE DOES THE POWER GO?

For example, the 26 foot vertical on 80 meters should be 66 feet high.
The "missing" 40 feet is replaced by coils (trap). This short antenna has a
radiation resistance of 4 ohms. It's a "virtual" resistor, which when power
is applied, radiates RF That, however, isn't the only resistor in the
antenna system. There are more. The significant resistor is called earth
loss, which is a function of the radials and ground. If three radials are
used, the earth loss created is more than 30 ohms. We now have an antenna
with 4 ohms that radiate and 30 ohms that warm the ground for a total of 34.
But only 4 ohms radiate! if 100 watts powers this antenna, only 12 watts
actually radiates. If you add lossey traps equaling 2 ohms, the power out
drops from 12 watts out to 11 watts out. While traps have their own
deficiencies, it is the huge earth loss that really matters. Fortunately,
GAP technology conquers this problem.